Propeller.



No. 654,549. Patented July 24. I900,

S. C. LITTLEFIELD, 1B. PROPELLEB.

(Application filed Dom 12, 1899.) (No Model.)

W/TNES S: INVENTOB ATTORNEYS r Norms PETERS co. wovmumon wuumcron, o. c.

rrrrnn Snares price.

PROPELLER.

SPECIFICATION forming part of Letters FatentNo. 654,549, dated July 24,1900. Application filed December 12, 1899. Serial Noi 740,055. (Nomodel.)

To all whom it may concern:

Be it known that I, SYLVANUS CLARK LIT- TLEFIELD, Jr., of Brunswick, inthe county of Glynn and State of Georgia, have invented a new and usefulImprovement in Propellers, of which the following is a Specification.

My invention relates to propellers, and has for its object apropeller-blade whose form will be such that it will reduce suction ordrag, will tend to throw the strain near the shaft, whereby to preventto a large extent lateral vibrationof the vessel, and which will nottend to settle the vessel deep in the water when at. high speed,- butrather lift and push the vessel, by reason of the fact that it willeffectively work when not Wholly submerged.

With these ends in view the invention consists in a propeller-blade ofthe specific form hereinafter described and claimed.

Reference is to be had to the accompanying drawings, forming part ofthis specification, in which- Figure 1 is a face view of my improvedpropeller-blade. Fig. 2 is a side View illustrating the blade whenviewed from the left as seen in Fig. 1. Fig. 3 is a side view of thesame when seen looking from the right of Fig. 1. Fig. 4 is a perspectiveview. Fig. 5 is an end view. Fig. 6 is a fragmentary section taken onthe line 6 6 of Fig. 1. Fig. 7 is a similar View on the line 7 f Fig. 1,and Fig. 8 is a longitudinal section on the line 8 8 of Fig. 1.

Referring to the drawings, A designates my improved propeller-blade,whose advance or attacking side edge a appears slightly outwardly curvedwhen looking toward a face of the blade, the curved portion extendingfrom the straight end edge B of the blade to the point a near the'hubportion 0, at which point the outwardly-curved portion merges into aninwardly-curved portion, as shown. The opposite edge a when viewing theblade as above stated appears with a pronounced inward curve from theend B to a point a from whence it takes on a pronounced outward curve,(designated by (L such outward curve extending to the hub portion 0, asshown, and serving to widen the blade con-= siderably from the line a; mto the line y y, the extent of this increase in width or bulge beingdenoted by the line .2 z. One face D of the blade is deeply concave, theconcavity at extending from the hub portion G to about the line as w andbeing deepest at the point 61 near the lower portion of the side edge a.The concavity cl merges into a slight outward sweep or trough-likeportion 61 beyond the line a: w, the said outward sweep being slight atthe point (1 of the blade and very pronounced at the opposite point (1The face D by its peculiar form provides a gradually deepening channelfor the water bounded approximately by the lines x no and y 3 forapurpose to be hereinafter described. The other face E of the blade isprovided with the portions e and e, corresponding substantially to theform of the face D, and the blade is slightly thicker at the hub portionthan at the end edge, as shown.

In general form the blade A is provided with a straight end edge, ismuch wider at a point near the hub portion, and the face D is convextoward the end and concave to- Ward the hub portion. By reason of havingthe said face convex at the end and concave in the center, running tothe hub portion, and by reason of the blade being wider near the hub thestrain 011 the blade is thrown near the shaft, giving more power for agiven steam-pressure. The blades being concave, as described, and widernear the hub force the water down the blades to the hub portions fromthe ends in the channel bounded by the lines cc at" and y y, whichcauses a large displacement of water and prevents suction and drag,which would tend to retard the vessel, and the blades being concave andwider at the hub portions gives the propeller great power, even if theblades are not wholly submerged.

The speed of the boat is governed by the pitch of the blades, and whenspeed alone is desired I preferably use two or three blades, while forspeed and power four blades are preferably used.

I wish it understood that my improved blades may be formed integral withthe hub of the propeller 0r adjustablethereon, as de sired.

Having thus described my invention, what I claim as new, and desire tosecure by Letters Patent, is

1. A propeller-blade having a straight edge B and a faceD formed withaconvex, troughlike or outwardly-sweeping portion (1 near the said endedge, the outwardly-sweeping portion being more pronounced at one sidethan the other, the said face D being also formed with a concave portiond merging into the portion 01 and being deepest near the hub of theblade, as set forth.

2. A propeller blade, provided with a straight end edge B, a slightlyoutwardly curved advance side edge a merging, into an inwardly-curvedportion a at the hub portion of the blade, an opposite side edge acurved inwardly from the end for a minor portion of ,its length andmerging into apronounced outward curve for the remainder of its length,and extending to the said hub portion, and a face D provided with aconcave portion d merging into a backwardlycurved trough-like orsweeping portion (1 as set forth.

A propeller-blade, having a straight end edge B, a slightly outwardlycurved advance side edge a, an opposite side edge a in wardly curvedfrom the end for a minor portion of its length and outwardly curved forthe remainder of its length to the hub portion of the blade, and a faceD concave from thehub portion to a point near the end and backwardlyturned from such point to the end, the concavity of such face beingdeepest near thehub portion, and the backwardlyturned portion of suchblade being more pronounced at the side edge a than at the side edge a,as set forth.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

SYLVANUS O. LIT'ILEFIELD, JR.

Witnesses:

G. B. CONYERS, C. P. GOODYEAR, J r.

